Self-Powering Gas Sensing System Enabled by Double-Layer Triboelectric Nanogenerators Based on Poly(2-vinylpyridine)@BaTiO<sub>3</sub> Core–Shell Hybrids with Superior Dispersibility and Uniformity
Jiyeon Oh, Jin‐Kyeom Kim, Jian Gao, Sungwoo Jung, W. K. Kim, Geunhyung Park, Jeewon Park, Jeong Min Baik, Changduk Yang
Abstract
Current core–shell hybrids used in diverse energy-related applications possess limited dispersibility and film uniformity that govern their overall performances. Herein, we showcase superdispersible core–shell hybrids (P2VP@BaTiO 3 ) composed of a poly(2-vinylpyridine) (P2VP) (5–20 wt %) and a barium titanate oxide (BaTiO 3 ), maximizing dielectric constants by forming the high-quality uniform films. The P2VP@BaTiO 3 -based triboelectric nanogenerators (TENGs), especially the 10 wt % P2VP (P2VP 10 @BaTiO 3 )-based one, deliver significantly enhanced output performances compared to physically mixed P2VP/BaTiO 3 counterparts. The P2VP 10 @BaTiO 3 -based double-layer TENG exhibits not only an excellent transferred charge density of 281.7 μC m –2 with a power density of 27.2 W m –2 but also extraordinary device stability (∼100% sustainability of the maximum output voltage for 54,000 cycles and ∼68.7% voltage retention even at 99% humidity). Notably, introducing the MoS 2 /SiO 2 /Ni-mesh layer into this double-layer TENG enables ultrahigh charge density of up to 1228 μC m –2, which is the top value reported for the TENGs so far. Furthermore, we also demonstrate a near-field communication-based sensing system for monitoring CO 2 gas using our developed self-powered generator with enhanced output performance and robustness.